This invention relates to a sealed paper shredder having continuous strippers that are integral with the housing.
In order to destroy documents to preserve their confidentiality, shredders exist which cut the paper into narrow strips. Typically, the cutting is achieved by a series of circular cutters which are arranged along the axis of two rotating members. The cutters of one rotating member are offset so that the cutters pass between the cutters of the other member.
The actual structure of the rotating members having cutters can be a solid bar of steel or similar material in which cutters and spacers are formed by machining so that the cutters and spacers are all integral to one another. Another structure has separate cylindrical members of a larger diameter which are used as the cutters and are spaced apart by separate cylindrical spacers which are assembled on a shaft in an alternating relationship.
One problem with known and existing shredding devices is that after the paper has been cut into strips, the strips tend to wind around the cutters and spacers, clogging the cutting area. To solve this problem it has been suggested to provide strippers to strip away the cut paper. Typically, the strippers consist of a serrated member or a comb type member having teeth that protrude in the spaces between the individual cutters. These members are located on the outward or post-shredder side of the cutting area. For example, U.S. Pat. No. 4,068,805 shows a comb means rigidly placed at the exit of the cutters and extending into at least one of the cutters.
Another method of providing a stripping means is shown in U.S. Pat. No. 3,033,064 which discloses a pair of combs each having a series of spaced teeth that project into the spaces between the cutters to remove the cut strips of paper. Each comb is rigidly mounted so that the teeth protrude into the side of the cutter shaft opposite of the cutting area. In addition, they are formed in a semi-circular shape so that they wrap around the series of cutters.
In addition, it has been suggested to provide a comb type member before the cutters. The comb then guides the uncut paper into the cutters. U.S. Pat. No. 4,018,392 shows a pair of combers attached to support rods, each comber having a tongue protruding forward of the cutters to comb and direct the material being fed to the cutting surfaces of the cutters.
The problem with these shredders and others is that a number of individual parts are required. Separate parts are required for the comb assembly and for mounting to the shredder housing. This increases the time and labor required to assemble the shredder which in turn increases the cost of the shredder.
A solution to these problems is exemplified in U.S. Pat. No. 5,071,080 assigned to the same assignee as the present application and incorporated herein by reference. In this patent, the shredder has upper strippers integral with the top housing and lower strippers integral with the bottom housing such that when the housings are joined, the upper and lower strippers substantially abut to define a continuous stripper. A potential problem may occur when the shredder is over-loaded causing the strippers and the housings to become separated.
The present invention prevents any potential separation by providing a sealed paper shredder having a top housing with integral upper strippers unremovably joined to a lower housing with integral lower strippers so that the upper and lower strippers are unremovably joined. The present invention also includes a method of manufacturing such a paper shredder.